Lovato, who has previously been treated for bulimia, took to Twitterto express her anger regarding the singer’s antics on stage. Lovato wrote: “@ladygaga you’re SO talented, if not one of the most talented in our industry PERIOD. Dope is INCREDIBLE. But you don’t have to do that.”

Gaga’s performance featured the singer being roasted above a grill before London-based performance artist Millie Brown came on stage and vomited paint on the singer.

Fans of Gaga tweeted Lovato reminding her that the singer revealed last year that she too suffered with an eating disorder. In response, Lovato wrote: “That doesn’t make it OKAY. If I do a speech about self-harm [can I] then proceed to watch people cut themselves on my stage? No.”

Lovato went on to tweet a longer statement regarding her feelings towards the performance, telling her followers that “bulimia isn’t cool”.

She wrote: “All I’m saying is, artists in pop culture have influence on people. Bulimia isn’t cool, and it won’t get you on stage with your favorite artist … [But] young people who are struggling to figure out their identities are seriously influenced by the things they see their idols do … [and] some of [them] are people who aren’t capable of understanding the art that is that is expressed by their idols.”

Millie Brown took to Twitter to defend her role in the show, writing: “I believe in absolute freedom of expression. Challenging perceptions of art and beauty. If your art is your communication it should not be censored.”